Mk4 Golf 1.8T 2004, has an issue with a consistent check engine light probably having to deal with this. These tubes coming from the fuel injection system I believe had been open.
VW Golf IV 4 GTI 1.8T 0-100 100-200 by Motorsportcheck - YouTube
Best Upgrades for your VW MK4 GTI 1.8T – ECS Tuning
Ramair intake kit for Golf MK4 GTI / TT 180 / Leon 1.8T 20V